In an effort to raise smart, successful children, parents will try anything, from baby videos to vitamins. But how can you tell marketing from real science? New research has revealed principles that might make you think again about what’s best for your child. Here are five common myths about children’s brains — as well as tips for doing better as a parent than the conventional wisdom.

Myth 1: Breast-feeding increases intelligence. It’s true that children who were breast-fed as babies have higher intelligence on average than other children. But it’s probably not the feeding itself — it’s the mother.

A mother with 15 more IQ points than her neighbor is more than twice as likely to breast-feed. Intelligence is partly genetically inherited and parental intelligence can also help create a more stimulating environment, two advantages for the baby’s development. In short: Smart mothers have smart babies.

Once these characteristics are factored out, researchers have found little or no effect on IQ associated with breast-feeding. Of course, breast-feeding still enhances the baby’s immune system, not to mention building a bond with mom. But you don’t need to worry about shortchanging your baby’s intellectual development with an occasional dollop of formula.

Feeding with soy or hydrolyzed-milk formula even has an unexpected benefit: Kids are more likely to accept vegetables such as broccoli at the age of 5. Why? Perhaps because baby learns to link the calorie content with bitter flavors — which turn up later in veggies.

Myth 2: Playing classical music to babies makes them smarter. This is one of the most persistent brain myths of all, even though the scientific evidence is completely lacking. It started in 1993 when researchers showed that college students who listened to a Mozart sonata did better on a complex spatial reasoning task. Like a game of telephone, this wasdistorted in the retelling. A self-help bestseller claimed that the “Mozart effect” influenced babies’ intelligence for years. Georgia governor Zell Miller played Beethoven’s “Ode to Joy” to his state legislature and got them to send $105,000 in classical music CDs to new parents.

Although passive listening will not make your child smarter, something else will: producing music. Learning to play a musical instrument increases IQ by about three points on average — a small but real improvement. The key difference is active engagement, which is essential to learning and intellectual development.

Myth 3: Pregnant women should avoid eating fish. Because exposure to mercury in the womb can harm a baby’s brain development, it was long believed that pregnant women should limit their consumption of fish. However, fish are also a major source of omega-3 fatty acids, which are crucial for normal brain development.

Indeed, prenatal deficiency of omega-3 fatty acids can lead to mental retardation. In one study, researchers interviewed 11,875 women during the third trimester and later tested their children’s cognitive abilities. Mothers who avoided seafood were more likely to have children with fine motor deficits, communication problems, poor social behavior and low verbal IQ. So while it’s a good idea to avoid top predator fish like swordfish and shark, which concentrate mercury in their tissues, other fish, especially salmon and sardines, are good for baby.

Myth 4: Baby videos improve brain development. On average, babies first watch TV at the age of 5 months. Marketers claim that videos like “Baby Einstein” and “Brainy Baby” can give your child’s brain a head start, but research shows the opposite. Before the age of 2, TV watching carries no benefit and is likely to do harm. Babies with more screen time know fewer words. A baby who watches two or more hours TV per day before the age of one is at six times higher risk for language delay.

If baby videos are bad, why does the baby like them so much? The quick cuts and bright colors seize their eyes. Yet exposure to fast-paced entertainment programs may interfere with the transition to voluntary attention, which happens after 10 months of age. Children who watch violent shows before age 3 are more than twice as likely to develop attention-deficit disorder.

Much better for the baby is to hear many words from real, live grown-ups. Talking to babies is most effective when the grown-up responds with excitement when the baby tries to say something.

Myth 5: Building self-esteem increases achievement. Despite the influence of the self-esteem movement of the 1970s, children do not benefit from the cries of “Good job!” that ring out over modern playgrounds. Children can detect empty praise from a mile away: After the age of 6, what they perceive is that the adult is not expecting very much.

“You’re so smart!” does not give your child any clue about what to do next time and can even reduce perseverance. Instead, give praise for specific actions. “Wow, you really worked hard on that math homework!” carries a clear message about the desired behavior. Providing high but achievable expectations will give your child the tools to achieve real success in the world — a proven route to true self-esteem.

Sandra Aamodt, a former editor in chief of Nature Neuroscience, and Sam Wang, an associate professor of molecular biology and neuroscience at Princeton University, are the authors of âWelcome to Your Childâs Brain: How the Mind Grows from Conception to Collegeâ (Bloomsbury), out this week.